class Solution {
public:
    int coinChange(vector<int>& coins, int amount) {
        int n = coins.size();
        vector<int> dp(amount + 1, 0x3f3f3f3f);
        dp[0] = 0;
        for (int i = 1; i <= n; i++)
            for (int j = coins[i - 1]; j <= amount; j++)
            {

                dp[j] = min(dp[j], dp[j - coins[i - 1]] + 1);
            }
        return dp[amount] == 0x3f3f3f3f ? -1 : dp[amount];
    }
};